Brake



T. W. WlTTY BRAKE Filed June 5. 1926 T. W. WITTY Nov. 9

BRAKEA Filed`June 51 1926 2 Sheets-Sheet 2 W.. N m T. T A.

Patented Nav'. 9, 1926.

UNiTEDsTA "THOMAS W. wrrcrur,- or LUIVERNE, MINNESOTA.

Application filed June 5,

This invention relates toa friction bralie mechanism designed primarilyl for use m Aconnection with the running gear of 'motor vehicles, but itis to be understood that a vlfriction brake mechanism, in accordancewith this invention, can be employed for any purposes for which it is found applicable, p and .the invention has for-its object to provide, in a manner as hereinafter set forth, a l lbrake mechanism including. a pair of oppositely disposed brake shoes for `frictional engagement with a brake --drum and with the shoes so constructed and arranged wherebyv on the application of pressure thereto it will 'A 15 be distributed evenly throughout the length thereof and under vsuch conditions provide for even wearing of the linings for lthe l `shoes thereby obtaining a much larger braking area resulting in a more effective longer 'Wearing brake mechanism.

Furtherl objects of the invention are tol provide, in a manner as hereinafter set forth, a friction brake mechanism for use 1n connection wlth the running gear of motor ve.-

.25 hicles and which is 'simple in its construction and arrangement, strong, durable, compact,

thoroughly efficient in its use, congeniently operated, readily installed .with respect to a brake drum, `and comparatively ,inexpensive 3.0 to set up.

' Withv he foregoing and'otl'ier objects in view,.the invention consists in the novel con'- struction, combination and arrangement of parts as hereinafter more specifically de 85 scribed and illustrated in the-accompanying, I

drawings, wherein is shown an embodiment of the invention, but it is to be understood v that changes, variations and modifications can Ibe resorted .to which fall -within the '4P scope of the claims hereunto appended.

In the drawings wherein like reference characters denote corresponding parts throughout the several views:

'Figure 1 is an elevation-of a friction brake mechanism, in accordance with Vthis invention, and showing the adaptation thereof in connection with a brake drum.

Figure 2 is a section on line 2-2 Figure 1. Figure 3 is an end elevation of an axle.: '50. section housing carrying aholder plate for the brake shoes. I

Figure 4 is an elevation of the shifting member for the brake shoe.

Figure 5 is a section on line-5-5 Figure 1. i Figure 6`is an elevation of one of the 'brake shoes.

and

1926. serial No-11a99'2.

Figure 7 is a top plan view of one-of the brake shoes. i

notes a brake drum which is adapted to be Vconnected-'to a vehicle wheel, not shown, or

to any other suitable support. Extending into the. drum 1 is a stationary housing 2 of a shivftable or revoluble axle section or shaft.

The axle section orbshaft is not shown. The houslng 2'at a point removed-from its outer end is formed with an annular flange Stof appropriate diameter and which .opposes and 1s spaced from the inner Wall of the drum 1..

The flangeB is slightly less in diameter than the inner diameter of the body portion 4 of y the drum 1. The body portion 4'of the drumv 1 overhangs the edge of the flange 3, see Fig- A ure-2. The flange 3 is termed a carrier and has its outer face formed with a pair of'diametrica-llyopposed pins or supports, 6 of oval shapein vertical section. The pin 5, as Well as thepin 6, isl of a length substantially Referring to the drawings in detail 1 de.-

half the width vof the body portion 4 ofthe drum and as lthe carrier 3 is positioned within the body. portion 4 the pin will project.,

forwardly" with respect to the vertical median of the body 4 in cross section, see F'ig-` ure 5. The carrier is circular in contour, as well asthe1 body portion 4`of the drum 1. When the carrier is mounted inopposed relation with respect to the inner Wall 'of the drum 1, the rear'face of the carrier is Hush with the rear edge of the body portion 4 of the drum, see Figure 2.

Shiftably mounted upon the housing 2 and withinthe bodyportion4 of the drum is a brake 'shoe actuating` member 7 of elliptical contour and which'is constructed of an elliptical shaped' plate formed with a centrally disposed circular opening. Theouter portion of the member 7 is enlarged as at 8 toprovide-forthe outer edge of they member lto be of greater widththan the in- 'ner edge thereof.' The said outer edge is indicated at 9. The member 7 is of a size with y.

respect to the diameter of the vbody portion 4 of the drum las to have its outer edgel towards each end thereof, see Figure 6. They collars 1() do not bind said member 7 to prevent the shifting therefrom to actuate 'the brake shoes, to be presently referred to.

' drum 1 and in cross-section is of less length than the length of said body portion 4 in cross section. The shank or Web 15 extends from one end to the other end of the body portion 14 and at each end of the shank or web 15 it is formed With a semi-oval shaped enlargement 16 to provide a pocket 17 The shank or web 15 gradually decreases in Width from the vertical median of the brake shoe shank or Web 15, centrally of its inner edge, is formed with an enlargement 18, hollowed to form a pocket 19 and with each side wall of said pocket formed With a semi-oval shaped notch 20. The notches of each enlargement 18 aline with each other. The functionl of the pocket 19 and notches 2O Will be presently referred to.

One side of the shank or Web 15, at a vpoint between the enlargement 18 and each pocket 17 is provided with an offset portion 21 formed with alateral pin 22. The pins 22 formed on one brake shoe aline With the pins 22 formed on the other brake shoe and each pair of alining pins are connected together by a. controlling spring 23. Arranged in each pocket 19 as Well as extending therefrom is a bearing roller 24 provided with pintles 25 which extend into the pair of alining notches 20. The controlling springs 23 maintain the rollers 24 against the outer edge 9 of the member 7.

Fixedly secured to the member 7 and projecting laterally therefrom is an arm 24 which extends through an arcuate slot 25 formed in the carrier 3 and said arm 24' is adapted to have its outer end attached to the control rod leading to the brake lever ofthe vehicle. The control rod is not shown. The member 7v is formed with an opening 26 in which is secured'the arm 24 and said meinber 7 is furthermore provided With a boss 27 and a sleeve 28 in which the arm 24 is secured. The arm 24 is provided With an enlargement' 28 vvhich'abuts against the free edge of the sleeve28. The outer end of the arml 24 is constructed, as indicated at 29, in a manner for securing it to the control rod leading to the brake lever.

The Vpockets 17 formed in the ends of one l brake shoe aline With the pockets 17 formed in the ends of the other brake shoe and extending through each pair of alining pockets is a pin or support 5 or 6. The pins 5 and 6 maintain the brake shoes in spaced relation with respect to each other. and fur- 1 thereby setting up a braking action. The

shape of the member 7 is'such, that in connection with the rollers 24 the brake shoes will move uniformly in opposite directions with respect to eachother so that the linings will evenly engage the body portion of' the drum or whereby on the applicationof pressure to the brake shoes it will be distributed evenly throughout the length thereof and under such conditions provide for even l Wearing of the lining for the shoes thereby obtaining a much larger braking area resulting in a more effective action. lWhen the control rod is released,the member 7 will be returned to normal position, which is as shown in Figure 1. This action is provided for in vieviT of the fact thatthe brake lever is spring released. The brake shoes are returned to normal position, that is tothe position shown in Figure 1, through the action of their controlling springs 23 or in other Words the brake shoes are spring released. The brake shoes automatically return to inactive position When the shifting member 7 is returned to normal position. l

It is thought the many advantages of aV friction brake mechanism, in accordance with this invention for the purpose referred to, can be readily understood, and although the vpreferred embodiment of the yinvention 'is as illustrated and described, yet it is to be understood that changes in the details of construction can be had which Will fall Within the scope of the invention as claimed.

What I cla-im is:`

1. A friction brake mechai'iisin'comprising a pair of oppositely disposed spring released brake shoes shifting to active position on the application of pressure thereto, a revoluble shifting member in the form of an elliptical plate surrounded by said shoes and acting .when shifted in one direction, to move said shoes in. opposite directions relatively to each other to active position, said shoes provided at their inner edges with rollers travelling against the outer edge of said plate when the latter is shifted, a pair of stop elements normally extending through the ends of said shoes and acting as supports therefor and stops for arresting the movenlent of said shoes towards each other, a

support for said stop elements, and means carried by said plate and extending through said'support for connecting the plate to an actuating means` therefor, said support formed with. an-arcuate slot coactingnith saidmeans. e

2.,A`friction brake mechanism comprising I a pair of oppositely disposed spring released 15'shifting member of. elliptical contour surrounded vby said shoes and `engaging said rollers to .move the shoes to applied position.

when said member is shifted-in one direction, means extending through the ends .of

said shoes for arresting the return movement thereof and further for supporting the shoes, a support or sa-ld'means, said -support formed with an arcuate slotand means.

carried by. said member and extending through said slot for connecting the member to an actuating means therefor.

In testlmony whereof, I ax my slgnature THOMAS W. WITTY. 

